i have just put in a graphics card (asus EN9800gt 512mb hybrid power) and wen i turn it on all i get is a black screen! what could the problem be? I have a 500w pc and its a very brand new pc with 64bit windows 7 and intergrated grraphics. also note that the first time i put it in i forgot to put in the 6pin adaptor and when i turned it on it made a big beeping noise. could this have stuffed up the card? becoz wen i remove it, the pc works fine help please???